1. Field of Invention
The present invention relates to the field of determining the physical location of a sensor. In particular, the present invention relates to a method, system, apparatus, and computer program product for determining a physical location of a sensor that relays information through a wireless radio network.
2. Discussion of the Background
Wireless communications have been adapted for many commercial uses. One use concerns the collection and relay of data from a distributed set of sensors to a central processing facility via one or more transmission and relay towers. In conventional systems, a sensor (e.g., a commercial utility power, gas, or water usage meter) is connected to a wireless transmitter. The transmitter relays information to a central account facility via a data collector or relay tower. The transmission time may be random or scheduled. If one or more transmitters are located out of range of the relay tower, repeaters are placed in one or more locations to receive and relay the transmission. Due to cost considerations, these repeaters often are not full duplex devices. That is, the repeaters often operate on a schedule where for a portion of time the repeater listens for a broadcast and then for another portion of time the repeater transmits whatever has been relayed. Additional periods exist where the repeater is neither receiving nor transmitting.
Background communication systems may be characterized by an inefficient flooding of information. That is, information sent by a sensor/transmitter may be received directly by a relay tower or data collector and still be repeated by one or more repeaters. What is desired, as recognized by the present inventors, is an efficient way to selectively relay information via a wireless transmission network.
Further, sensor devices in a background remote metering system, or other telemetry system, may be misplaced or stolen and installed in a location that is unknown to the system operator. While the system operator may quickly detect the absence of the sensor device, or a tamper alarm, the physical location of the sensor device is often extremely difficult to pinpoint. In addition, this problem is compounded by the fact that background systems make it possible to collect sensor information without having a person visit the sensors and verify their locations. What is further desired, as recognized by the present inventors, is an efficient way to determine the physical location of a sensor device.